Available in Chrome 87+ | View on GitHub | Browse Samples
The Web Bluetooth API lets websites discover and communicate with devices over the Bluetooth 4 wireless standard using the Generic Attribute Profile (GATT). It is currently partially implemented in Android M, Chrome OS, Mac, and Windows 10.
This sample illustrates the use of the Web Bluetooth API to read out advertisement data from nearby Bluetooth devices. You may want to check out the Watch Advertisements sample.
async function onWatchAdvertisementsButtonClick() {
try {
log('Requesting any Bluetooth device...');
const device = await navigator.bluetooth.requestDevice({
// filters: [...] <- Prefer filters to save energy & show relevant devices.
acceptAllDevices: true});
log('> Requested ' + device.name);
device.addEventListener('advertisementreceived', (event) => {
log('Advertisement received.');
log(' Device Name: ' + event.device.name);
log(' Device ID: ' + event.device.id);
log(' RSSI: ' + event.rssi);
log(' TX Power: ' + event.txPower);
log(' UUIDs: ' + event.uuids);
event.manufacturerData.forEach((valueDataView, key) => {
logDataView('Manufacturer', key, valueDataView);
});
event.serviceData.forEach((valueDataView, key) => {
logDataView('Service', key, valueDataView);
});
});
log('Watching advertisements from "' + device.name + '"...');
await device.watchAdvertisements();
} catch(error) {
log('Argh! ' + error);
}
}
/* Utils */
const logDataView = (labelOfDataSource, key, valueDataView) => {
const hexString = [...new Uint8Array(valueDataView.buffer)].map(b => {
return b.toString(16).padStart(2, '0');
}).join(' ');
const textDecoder = new TextDecoder('ascii');
const asciiString = textDecoder.decode(valueDataView.buffer);
log(` ${labelOfDataSource} Data: ` + key +
'\n (Hex) ' + hexString +
'\n (ASCII) ' + asciiString);
};